Transcript for 911 Call Released in Florida Professor's Death Investigation

mysterious murder of a prominent law professor. Police releasing the dramatic 911 call from a neighbor saying Dan Markel had been shot in his car revealing how long it took for help to arrive. Matt Gutman is tracking the case from Miami. Good morning, Matt. Reporter: Good morning. Also revealing those last agonizing moments of Dan Markel's life, the father of two trapped in his car bleeding unable to talk as his neighbor dialed 911 urging rescuers to move faster because Markel was alive. Emts like to say seconds count but it took them nearly 20 minutes to get there. This morning the harrowing moments after a Florida state law professor Dan Markel was gunned down in his garage. The driver's side window is all bashed in and he's got blood all over his head. Reporter: Markel still breathing during this 911 tape released Thursday. He's still moving around. So he's alive. Reporter: 12 minutes later the caller still urging the 911 dispatcher to move faster. You need to send an ambulance in a hurry. The response. The officer is going to be there first. They're not going to come until we figure out what's going on. They better be if this guy's got a shot. Reporter: He was shot as he drove his car into his garage on July 18th. Sources telling ABC news the killer fired a single bullet through the driver's window hitting Markel just beneath the jaw line. The killer and motive still unknown. But that caller noting he happened upon Markel's car because he had been worried about an uptick in crime. I've heard about break-ins in the area and so I decided to walk over and take a look. Reporter: We learned 19 minutes passed before that good samaritan's call and the paramedics' arrival. Markel would die 14 hours later in the hospital. In that call you can hear the confusion. I'm changing the location -- The police needs to go. Reporter: The man who runs Tallahassee's dispatch center tells ABC news the operator didn't hear the caller mention the gunshot wound at first. On the onset it was entered into the computer system as a man down versus a gunshot wound. Reporter: All of that creating a toxic brew of confusion and delay in the response as one ems unit was replaced by another. 19 minutes is a long time for making changes in this review to make sure this doesn't happen again. Reporter: Of course, the police investigation continues. Now, law enforcement officials tell me that the tips keep coming in and they hope that this 911 call will generate even more tips. Now, the main focus of the investigation remains that mysterious silver prius that was seen speeding by -- from the scene just moments after the shooting by another neighbor. George. Okay, Matt, thanks very much. Dan Abrams joins us now. Boy, that is one frustrating and sad phone call. Not the way it's supposed to happen when you call 911. You're talking about a 19-minute response time. The average response nine is under 9 minutes so this just shows you how much time was lost in getting there. Now, I don't think that's going to impact the investigation. But there's no question that the possibility it could have saved his life. On the investigation, you are actually surprised he haven't identified someone yet. It was so targeted here of the it was so clear that someone wanted to kill him. It doesn't seem it was robbery. It seems that this was an execution and as a result, these cases tend to get solved. They tend to look at the inner circle of that person and are able to resolve the case pretty quickly. Here it now seems the authorities are expanding way beyond the inner circle to say to themselves could it have been someone he might not have even known. Could it have been someone associated with or commenting on his blog, et cetera, all these possibilities that make it such a harder case. Yeah, that is one thing you thought from the beginning much they were initial going for people that they thought knew him but now they have to get bigger. That's the way you do the investigation. Start with the people closest to him. Then you look out and that's why again as Matt pointed out that prius becomes so important because it's the only hard clue that they have that might be able to link them back to the person. Such an unusual getaway car. Yeah, we talked about this before. The notion that, you know, someone is using a prius as a sort of execution vehicle, if that's what it was, again, we don't know. They respect saying that they know for sure but they are very, very interested in finding out would was driving that car. Okay, Dan Abrams, thanks very

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